Spiritual growth is kind of an intangible concept which has to be experienced.

Can you use it to learn other things? Sure, I really don't see why not.However, you're time while non-physical is usually very limited... and using it to learn "math", just doesn't seem the best use of the knowledge of the universe.

The ability to become lucid is a state and so in itself not useful unless you apply it so it is no use getting lucid in a dream and learning, creating and exploring if you dont take the overall attitude as well as the growth and learn to become lucid in daily life as well. The difference in how you feel between a vivid dream and a lucid dream can be applied to waking life and you can experience this world in a better way.

Who are you I asked, the reply "dont be silly, we are your daughers" many years before they were born

Hello everyone, I registered today only, i have no experience on lucid dreaming, once just got aware in my dream for couple of seconds. But i really want to do it once, and i know this forum can definitely help me.

Guys, check this book out! Lots of examples of how you can use lucid dreaming in life:http://www.world-of-lucid-dreaming.com/forum/viewtopic.php?f=11&t=1726

It's Robert Waggoner's Lucid Dreaming: Gateway To The Inner Self.

I also recommend LaBerge's Exploring the World of Lucid Dreaming

"Empty cognizance of one taste, suffused with knowing, is your unmistaken nature, the uncontrived original state. when not altering what is, allow it to be as it is, and the awakened state is right now spontaneously present."

i wouldn't exactly say its useful as far as building skills, but i find lucid dreams "useful" because they really allow you to augment your life in general. think about it anything that you wouldn't do in real life because of fear of danger you can do in a LD. also things that you couldnt to at all because of there lack of bieng physicaly possible i.e. flying un-aided , using portals , morphing into other creatures.

I think it has helped me, personally. One, I dont get bored with life like I think we all do at times. When stuck in some mundane situation I practice reality checks and consider what exciting thing to do in my next LD which is hopefully that night. Two, going to bed is seen as a beginning of exploration not the end of a day. I feel I get more out of life. Three, fear of death is much less since a spiritual existance without a body has already been experienced. Four, I question reality more which means dumb rules dont hamper me as much as before. And frankly I can be more forgiving and less envious... heck, I consider LDs a priceless gift others who have more physically would envy me for, if the understood what I can do... its like having a super power!